Banner considerations have evolved immensely in past few years from my own observations. Only a few years ago items we see routinely these days were making banners all the time ie Spanish reales and such, of course, significant finds were too; but nowadays it's the cream of the crop making it, as it should be. Extremely rare and obscure finds weren't brought to the forefront as readily. We can now attribute better banners with shared knowledge and better posting guidelines to help identify these finds. But it all boils down to what the general voting public want to see. These days people pull the banner trigger without hesitation, although not all finds are considered, many are still voted for without knowing or showing the background and significance of the find. Even having said that, many great finds just don't get enough recognition in their own respect, a good example might be finding a super military button the day someone else posts say a cache of gold coins, gems get buried and shoved out the spotlight. One might call that one the downsides to being part of a huge detecting community such as this one.
Best way to have/ make banners is to be lucky enough to make the finds and be a good "salesman" for your product(find); it's not going to get easier from what I've been seeing, only a little more difficult, which I feel is good. So, hopefully we can see some more awesome finds up top and hopefully another nice old rare state copper soon!